Centrifugal compressor



July 7, l942- c. H. AUGER ETAL 2,289,231

CENTRIFUGAL COMPRESSOR Filed Jam.v 18. 1940 2 sheets-shawl Figi.

Inventors# Clude H ALlQeP, Wayne H.A|Ie1,

b WW

ilrnem'* Attorney I frail/45545 July 7, 1942.

c. H.VAUGER ETAL. CENTRIUGAL COMPRESSOR 2 Sheets-Sheet 2 Filed Jim. 18,1940 Pigs.

A filiali MIJ/III Inventors: Claude HAuggeT, Wayne H. AI len, www5/MWI@'Then Attorhey.

Patented July 7, 1942 CENTRIFUGAL COMPRESSOR.

Claude H. Auger, Saugus, and Wayne H. Allen, Lynn, Mass., assigner-s toGeneral Electric Company, a. corporation of New York Application January1s, 1940, serial No.l 314,466

7 Claimsl.`

The present invention relates to centrifugal compressors or blowers suchas are used for supercharging internal combustion engines. Suchcompressors comprise an impeller disposed in an impeller chamber forimpelling a compressible medium such as air and forcing it into acollector passage or discharge scroll. Ordinarily a diiuser isinterposedl between the impeller chamber and the collector passage forconverting velocity energy of the medium impelled bythe impeller intopressure energy. In many cases, especially where such superchargers areused in connection with aircraft, it is desirable to keep their radialdimensions at a minimum.

The object of our invention is to provide an improved construction andarrangement of centrifugal, compressors whereby the radial dimensionthereof may be considerably reduced.

Heretofore it has been customary to provide a collector passagesurrounding the diuser and extending in 4radial direction considerablybeyond the diffuser. According to our invention the collector passage isarranged laterally adjacent the'diiuser.l In one embodiment thedischarge, scroll ,is` entirelyI Von one side of the diffuser while thediffuser vanes extend radially tothe outer periphery ofthe casing. -Inorder to effect smoothl'discharge fro'm such diuser into the collectorpassage, the outer portion of one diiuserside wall has openings adjacentthe collector passage and the otherside Wall of the diffuser is smoothlycurved towards the collector passage.r

For a better understanding of what we believe 'to benovel and ourinvention, attention is dlrected to the following description and theclaims appended thereto in connection with the accompanying drawings. l

In the drawings, Fig. 1 illustrates a sectional .view of a centrifugalcompressor in accordance van enlarged sectional view along the curvedline 6-6 of Fig. 5; and Fig. 7 is an enlarged sectional view along thecurved line 'I-'I of Fig. 5.

The arrangement comprises a casing having two halves I and II flangedtogether by bolts I2. The casing half I0 forms an inlet opening I3 curedto the shaft b'y means including a nut I1.

The shaft I5 with thel impeller I6 is driven by a suitable power agency,not shown. i During operation the compressible medium is drawn into theinlet I3 and forced outward by the impeller at/ considerable velocity.The velocity energy of the medium thus impelled is-partly converted intopressure -energy by a diiuser I8 concentrically surrounding the impellerI6 and inthe present instance integrally formed with the casing half I0.The compressed medium is discharged from the diifuser into a-collectorpassage or scroll IS which in the'present instance is formed bythe'casing half II and arranged substantially `entirely laterallyadjacent the diifuser.

The 'di-Iuser has a plurality of vanes 20 forming diffuser passages 2|between them. One side wall of the diffuser facing'away from thecollector passage is formedby the casing half I0 and hasan outer portion22 curved towards the collector passage I9 to effect smooth discharge ofcompressed medium. Another side wall 23 of the diffuser adjacent thecollector passage I9 has an outer portion with openings 2l through whichcompressed medium is discharged from the diffuser passages into thecollector passage I9. The

. side wall 23 is seated on a shoulder formed by the casing half II.From another viewpoint, it will be noted that the collector passage isdened between an outer portion of the casing half II and the side wall23 of the diffuser, and the outer diameter of the collector passage isabout equal to the outer diameter of the diffuser. Portions of the twocasing halves I0 and II form a flanged opening 25. The y portion of theside wall 23 beyond the outer tips of the dilfuser vanes 20 iscompletely removed within the flanged opening 25 so that the side wallin this opening assumes a saw-tooth shape similar tothe arrangementdescribed in the Patent No. 2,042,550 to S. R. Puffer and assigned tothesame assignee as the present application.

In the arrangement shown in Figs. 1 to 3 the discharge scroll is locatedsubstantially entirely on one side of the diifuser.

located laterally adjacent both sides of the diffuser. The compressor ofFigs. 4 to 7 comprises a casing having two anged halves 30 to SI boltedIn the vmodificationv 'shown in Figs. 4' to 7 the discharge scroll isThe easing half 3| forms an inlet 32 present instance integrally formedwith, side walls 31 and 38. The side walls are seated on shoulders 39,40 formed by the casing. The vanes project outwardly into proximity ofthe outer ends of the side walls and inwardly beyond the inner ends ofthe side walls, that is, beyond the shoulders 39, 40. These inner endsare engaged sidewise by the inner surfaces of the casing halvesCompfessed medium passed through the diffuser is discharged into adischarge scroll formed by the casing. More specifically, the dischargescroll includes two channels or passages, a channel 4| defined betweenthe side wall 31 and an outer portion of the casing half and a passageor channel 42 formed between the side wall 38 and an outer portion ofthe casing half 3|. The two channels or discharge passages 4|, 42 mergeinto a flanged outlet 43 formed by the casing. Here, as in thearrangement described above in connection with Figs. 1 and 3, the outerdiameter of the discharge passages 4|, 42 is about equal to the outerdiameter of the diffuser. The diffuser discharges into the channels 4|,42 through two sets of sidewall openings 43 and 44, connecting alternatediffuser passages with the channels 41 and 42 respectively, that is,alternate passages'formed by the diffuser vanes are connected byopenings 44 in the side wall 38 with the channel 42 and the otherpassages formed between the vanes are connected by openings 43 in theside wall 31 with the channel 4|. Hence, the diffuser passages formed onopposite sides of each vane discharge through openings in the oppositeside walls 31, 38 into the channels 4|, 42 respectively. The side wall31 has outer portions 45 opposite to and curved towards the openings 44in the side wall 38 to effect smooth lateral discharge from the diffuserinto the channel 42. Likewise, the side wall 38 has outer portions 46opposite to and curved towards the openings 43 in the side wall 31 toeffect smooth discharge of compressed medium from the diffuser into thechannel 4|.

Having described the method of operation of our invention, together withthe apparatus which we now consider to represent the best embodimentthereof, we desire to have it understood that the apparatus shown isonly illustrative and that the invention may be carried out by othermeans.

What we claim as new and desire to secure by Letters Patent of theUnited States, is:

1. Centrifugal supercharger comprising a casing forming an impellerchamber, an impeller disposed in the chamber, a diffuser surrounding theimpeller and having side walls with a plurality of vanes between them,outer portions of one side wall forming openings and outer portions ofthe other side wall being curved towards said openings, and a collectorpassage for receiving compressed medium from the diffuser through saidopenings, said entire passage being arranged laterally adjacent thediffuser and having outer sage` beingisubstantially equal and the outerportion of one side Wall-forming openings for conducting compressedfluid from the diffuser to the collector passage and outer portions ofthe other side wall being curved towards said openings to effect smoothdischarge of fluid.

3. Centrifugal compressor comprising a casing forming an impellerchamber, a diffuser with a row of vanes concentrically surrounding theimpeller chamber and partly formed by the casing, a collector passageformed partly by the casing and the diffuser and located laterallyadjacent the diffuser, the diffuser having a side wall adjacent thecollector passage with openings in the outer portion only of the wallthrough which compressed medium is discharged from the diffuser into thecollector passage and another side wall facing away from the collectorpassage with an outer portion curved towards the passage in thedirection of fluid flow to effect smooth discharge of compressed medium,said diffuser vanes extending radially to the inner surface of thecurved side wall portion.

4. Centrifugal compressor comprising a casing forming an impellerchamber, an impeller disposed in the chamber, a diffuser surrounding theimpeller and having side walls and a plurality of circumferentiallyspaced vanes extending to the outer Wall of the casing, and a scroll forreceiving compressed medium from the diffuser, said scroll being formedby two channels on opposite sides of the diffuser and having outerradial dimensions substantially equal to those of the diffuser, andmeans for smoothly conducting fluid from the passages into the scrollcomprising axially curved walls forming continuations of the side wallsand enclosing outer portions of the passages and openings formed in theouter portion only of a side wall of each passage.

5. Centrifugal compressor comprising a casing forming an impellerchamber, an impeller disposed in the chamber, a diffuser surrounding theimpeller and having side walls supported on the casing, and a pluralityof vanes formed on the side Walls and defining diffuser passagestherewith, outer portions of each side wall having openings and adischarge scroll for receiving compressed medium from the compressorcomprising two channels, a first channel formed between one side walland one casing half, a second channel between the other side wall andthe other casing half, said channels communicating through the openingsin the side walls with different diffuser passages, and an outer wallforming continuations of the side walls and substantially closing theouter ends of the diffuser passages and hav.

ing axially curved portions smoothly to direct fluid through theopenings into the channels.

6. A diffuser for centrifugal type compressors comprising a plurality ofcircumferentially spaced vanes, and side walls secured to opposite endsof the vanes and definitely secured to opposite ends of the vanes anddefining diffuser passages therewith, outer portions of one side walhaving openings for discharging compressed medium from alternate'diffuser passages, the other side Wall having an outerportion withopenings for discharging compressed medium from the other passages, andeach side wall having outer portions substantially closing the ends ofalternate passages and curved towards the openings in the other sidewall to effect smoth lateral discharge from said alternate diffuserpassages.

7. Centrifugal compressor comprising a casing forming an impellerchamber, an impeller disposed in the chamber, a diffuser concentricallyspaced with the impeller and comprising' a plurality of circumerentiallyspaced vanes and side walls secured to opposite ends of the vanes anddening diffuser passages therewith, outer portions of one side Wallhaving openings for dis-A charging compressed medium from alternatediffuser pasages only, the other side wall having an outer portion withopenings for discharging compressed medium from the other passages only,each side wall having outer portions curved towards the openings in theother side wall to effect smooth lateral discharge from the diffuserpassages, and a discharge scroll for receiving compressed mediumdischarged from said openings comprising two channels, a rst channelformed between one side wall and an outer portion of the casing and asecond channel formed between the other side wall and another outerportion of the casing, the outer dimensions of the discharge being aboutequal to those of the outer dimensions of the diffuser.

CLAUDE H. AUGER.

WAYNE H. ALLEN.

